Siemens 7SR18 Solkor - Thermal Overload; Reference; Operate and Reset Level; Operate and Reset Time

7SR18 Performance Specification
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2.3 49 Thermal Overload
2.3.1 Reference
Parameter Value
Is Overload setting 1.0 xIn
i Applied Current (for operate time) 1.2 to 10 x Is
τ
Time constant setting 1, 10, 100, 1000 min
2.3.2 Operate and Reset Level
Attribute Value
I
ol
Overload level
100 % Is, ± 5 % or ± 1% In
Reset level
≥ 95 % I
ol
Repeatability
± 1 %
Variation
-10 °C to +55 °C
≤ 5 %
f
nom
± 5 %
≤ 5 %
2.3.3 Operate and Reset Time
Attribute Value
t
op
Overload trip operate time
( )






×−
−
×τ=
2
2
2
P
2
I
II
ln
B
Ik
t

where I
P
= prior current
±5 % or ±100 ms
Repeatability
± 100 ms
Note:- Fastest operate time is at 10 xIs